Rotary liquid distributor



Dec. 20, 1955 E. M. KELLY 2,727,785

ROTARY LIQUID DISTRIBUTOR 2 Sheets-Sheet 1 Filed Oct. 18, 1954 IN V EN TOR.

j 54m. M. KELLY Q l 1 y L 33 l E. M MM N ATTORNEYS Dec. 20, 1955 E. M. KELLY 2,727,785

ROTARY LIQUID DISTRIBUTOR Filed Oct. 18, 1954 2 Sheets-Sheet 2 INVENTOR. EARL M KELLY United States Patent ROTARY LIQUID DISTRIBUTOR Earl M. Kelly, Burlingame, Califi, assignor to Process Engineers Incorporated, San Mateo, Calif., a corporation of California Application October 18, 1954, Serial No. 462,650

9 Claims. (Cl. 299-69) This invention relates to apparatus for distributing liquid over filter beds and the like.

In conventional rotary liquid distributors, liquid is sprayed over a filter bed by hollow radial arms carried by a central well rotatably disposed on a stationary influent column. The arms are provided with a plurality of spaced liquid discharge openings arranged to discharge liquid in a substantially horizontal direction. The reaction of the flowing liquid causes the arms and center well to rotate about a vertical axis. The dimensions of the structure and the discharge openings are usually designed to operate most efficiently under a predetermined hydraulic head in the center well. In many types of installations, e. g., at sewage plants, the total flow delivered to the rotary distributor will vary widely, and thus cause the hydraulic head in the center well to change, which results in inefiicient operation of the distributor.

This invention overcomes this difi'iculty by providing a rotary distributor which will accommodate a wide range of flow rates by using a weir arrangement associated with the center well which maintains the desired hydraulic head and permits the excess flow to be distributed efficiently. Furthermore, the invention provides a weir arrangement in which the weir can be readily designed to any desired length to reduce to a minimum the loss of hydraulic head in liquid flowing over the weir.

The rotary distributor of this invention comprises a hollow central well-adapted to receive liquid and rotate on a stationary base. A weir box is attached to the well and extends outwardly from it. An upwardly extending weir divides the weir box into two compartments, one of which opens directly into the well and the other of which is sealed from direct communication with the well. A liquid distributing arm extends outwardly from the box and is divided by a partition into two longitudinal flow sections. One of the flow sections opens into one of the weir box compartments and the other section opens into the other weir box compartment. Each of the flow sections is provided with a plurality of spaced liquid discharge openings so that liquid is discharged in substantially the same horizontal direction to cause the arm and center well to rotate.

In a preferred form, the distributor is provided with a plurality of radially extending and equally spaced weir boxes and arms to facilitate balancing of the well on the base. The upper edge of the weir in each box is provided with an adjustable strip whereby the effective weir height can be regulated. An orifice and valve arrangement are provided in the intermediate part of each weir so that some liquid can be by-passed through the weir if desired.

These and other aspects of the invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings in which:

Fig. l is a fragmentary plan view of the presently preferred embodiment of the invention;

Fig. 2 is a sectional elevation taken on line 2-2 of Fig. 1;

2,727,785 Patented Dec. 20, 1955 Fig. 3 is a sectional view taken on line 3-3 of Fig. 1; Fig. 4 is a sectional view taken on line 4-4 of Fig. 1; Fig. 5 is a sectional view taken on line 5--5 of Fig. 1 showing an alternate arrangement in which the order of operation of the flow sections in the arms is reversed from that illustrated in the apparatus shown in Figs. 1 through Fig. 6 illustrates an alternate arrangement for the weirs and partitions taken on a line similar to 3--3 of Fig. 1; and

Fig. 7 is a transverse sectional elevation of an alternate arm embodiment that may be used with the weir of Fig. 6.

A liquid rotary distributor 10 shown generally in Figs. 1 and 2 is arranged to rotate clockwise as viewed in Fig. 1. Incoming sewage or other liquid to be treated is introduced up the interior of an upright, hollow, concrete pier 11 projecting up through a filter. bed 12 made of conventional rock or aggregate.

Referring to Fig. 2, an annular upright stationary base member 13 is rigidly attached about the opening in the pier by means of nuts 14 and threaded anchor rods 15 embedded in the upper end of the pier. An annular bearing flange 16 having an upwardly opening bearing channel 17 is integrally formed about an intermediate portion of the base. A large diameter main bearing 18 is in the .bearing channel.

An upright, hollow, cylindrical central well 19 rotatably disposed on the base is provided with an inwardly turned flange 20 which rides on an annular race 21 supported by the upper part of the main bearing. Four equally spaced downwardly extending skirts 22 are provided on the outer periphery of the annular race. A separate stabilizing roller 28 is carried by each skirt and extends inwardly to bear against the underside of the annular bearing flange on the base to prevent tilting of the rotatable well. The inwardly turned flange at the lower end of the well carries a conventional annular seal 31 which extends inwardly and seats on the upper end of the base to form a liquid tight seal between the base and the well.

Four equally spaced, radially extending, rectangular weir boxes 33 are attached to the side of the well. Each weir box is open at the top and a reinforcing strip 34 of angle iron is welded along the upper edges of each box. An upright wall or weir 35 is longitudinally disposed along the center line of each box to divide the box into a leading compartment 36 on the leading side of the box and a trailing compartment 38 on the trailing side of the box. The upper edge of the weir starts below the top of the box and extends vertically to a position near the bottom of the box and then is curved rearwardly at its lower edge to seal against the interior of the trailing side wall 39 of the weir box. A pair of laterally spaced upper discharge openings 40 are provided in the trailing wall of the weir box just above the lower edge of the weir. A pair of laterally spaced lower discharge openings 42 are provided in the trailing wall directly below the upper openings and below the lower edge of the weir. The weir box openings are located over the filter bed and are arranged to direct liquid in a lateral direction, i. e. transverse to the direction in which the box extends. A spreader plate 44 (Fig. 3) is attached to the bottom of the box to extend rearwardly under the two openings.

A square orifice 46 is provided in the central portion of each weir and is controlled by a gate valve 48 arranged to slide vertically in guide slots formed by a separate vertical Z strip 49 welded on each side of the orifice. A lifting arm 51 and handle 51 extend from the valve above the top of the weir box so that the orifice can be either closed or opened to any desired position, as may be required. A longitudinal vertically adjustable weir strip 52 is attached to the upper edge of the weir by means of adjustable strip at the top of each weir.

3 bolts 53 extending through matching vertical slots 54 in the strip.

In the embodiment illustrated in Figs. 1 through 4, the inner end of each leading, compartmentin each weir is connected by a pair of vertical diverging plates to an opening'56in the well wall. With this arrangement, the leading compartment serves as a primary compartment and the trailing compartment serves as a secondary compartment, i. e., the leading compartment receives liquid before the trailing compartment.

The inner end of a separate radially extending hollow arm 58 is attached to the outer end of each box by means of a flange and bolt connection 59. Each arm is supported by guy wires.60 attached to a conventional central mast structure 61 erected on and extending above the centerwell. Conveniently, each arm is of almost square cross section and is made in relatively short sections from steel plates. The sections are held together by bolts and flanges at their respective ends. The outer end of each arm is sealed by a blank plate 62. The bottom of each arm is horizontal, but the top of each arm tapers downwardly with increased distance from the well to give a continually decreasing cross-section of flow area.

Each arm is divided into two longitudinal flow sections, a leading flow section 64 and a trailing flow section 65, by a partition 66 which extends throughout the length of each arm and extends from the center line of the top of each arm toward the bottom of the arm. The upper portion of the partition is vertical and the lower portion is curved rearwardly and is attached to the lower part of the trailing wall of the arm a short distance above the bottom of the arm. This arrangement of the partition increases the rigidity of the arm. The leading section opens into the primary compartment of the weir box, and the trailing section opens into the secondary compartment of the weir box, and serves as primary and secondary flow sections, respectively. A series of longitudinally spaced liquid discharge openings 68 are provided in the trailing wall of each flow section. The openings are aligned vertically in pairs and a spreader plate 70 is attached to the lower edge under each pair of openings.

The apparatus illustrated in Figs. 1 through operates as follows: The liquid infiuent enters the center well and flows outwardly into the primary compartment of each weir box as indicated by the arrows in Fig. 1. Under moderate rates of flow, the hydraulic head builds up in each weir box to a height slightly below that set by the The liquid flows from the primary weir compartments into the primary flow sections of the arms is discharged through the primary section openings in a rearward direction and causes the distributor to be rotated in clockwise direction, as viewed in Fig. 1. If the total liquid flow into the central well is increased, the liquid in the weir boxes rises to the level established by the adjustable weirs, flows into the secondary compartment of the weir boxes and then into the secondary sections of the flow arms to be discharged out the secondary section openings in a rearward direction. The spreader plate under each pair of openings spreads the liquid out in a fan-like pattern so that the filter bed is covered uniformly by the discharged liquid. Thus, the liquid is delivered to the discharge openings in the primary sections under a substantially constant head designed for proper hydraulic action and operation even though the flow rate may vary considerably. The excess flow is spread efficiently by the secondary. sections of the arms.

In the .event it is desirable to have the secondary sections of the arms operate at relatively low flow rates, the gate-controlled orifice in the weir is opened either partially or completely, as desired, to allow liquid to pass into the secondary compartment of the weir box, even though the liquid head has not built up sufficiently to flow over the top of the weir. In this condition all compartments of the arm are then in operation under the relatively low flow rates.

An alternate arrangement of the apparatus shown in Figs. 1 through 4 is illustrated in Fig. 5 in which the inner end of the trailing compartment 72 of each weir box is connected to an opening 73 in the well wall by a pair of vertical divergent plates 74. In this arrangement,

a the trailing compartment fills first to distribute liquid to" the flow section on the trailing side of'the flow arms. The curved portion of both the weirs and the partitions serves to convert the direction of water flow from vertical to substantially horizontal with a minimum hydraulic head loss.

Fig. 6 is a vertical section (looking outwardly) of an alternate arrangement for the weirs and partitions in the rotary distributor. In this embodiment each box 76 has a vertical weir 77 which extends longitudinally along the center line of the box for the length of the box and from the bottom of the box to terminate below the top of the box, thus dividing the weir box into a primary compartment 78 on the leading side of the weir and a secondary compartment 79 on the trailing side of the weir. The inner end of the primary compartment opens directly into the well, and the inner end of the secondary compartment is sealed from direct communication with the well by the well wall. A discharge opening 80 in the bottom edge of the trailing weir wall opens rearwardly over a spreader plate 81. An arm 82 of almost square cross section (see Fig. 7) extends outwardly from the outer end of each weir box and is divided into a primary section 83 on the leading side of the arm and a secondary section 84 on the trailing side of the arm by a partition 35 which extends for the length of the arm and is disposed di agonally across the interior of the arm. The leading edge ofrthe partition begins slightly below the upper edge of the leading wall of the arm and the trailing edge of the partition terminates just above the lower edge of the trailing wall of the arm. The outer ends of the primary and secondary compartments in the weir box are respectively connected to the primary and secondary sections in the arm, and the arm is provided with the discharge openings and spreader plates as described for the embodiments of Figs. 1-4.

The operation of the liquid distributor as illustrated in Fig. 6 is similar to that of the embodiment shown in Figs. 1 through 4. The primary compartment in the weir box fills up first to deliver liquid to the primary section of the arm. As the liquid builds up and overflows the weir box, the secondary compartment in the weir box fills up and delivers liquid to the secondary section of the arm. Some of the liquid in the secondary 1cjompartment is discharged out the opening in the weir In all of the above described embodiments, the use of a substantially vertical or diagonal partition in the arm increases the stiffness of the arm and reduces the tendency of the arm to sag or bend in a vertical direction.

The use of the plurality of radially extending weir boxes and weirs makes it possible to reduce hydraulic head loss over the weirs by simply extending the length of the weir boxes. if relatively long boxes are required to reduce head loss, the boxes become, in effect, distributing arms and may be provided with a plurality of dischar e orifices of the type illustrated in Figs. 3, 5 and 6.

Although the specific embodiment described above employs four weir boxes and four arms, each of which is divided into two compartments and flow sections, respectively, any number of boxes and arms may be used and they may be subdivided into any reasonable number of compartments and sections.

I claim:

1. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending outwardly from the well, an upwardly extending weir dividing the box into two compartments, one of the compartments opening directly into the well, and a liquid distributing arm extending outwardly from the box, the arm having at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the Weir box compartments and the other section opening into the other weir box compartment.

2. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a plurality of equally angularly spaced weir boxes attached to and extending outwardly from the Well, each box having an upwardly extending weir dividing the box into two compartments, one of the compartments opening directly into the well, and a liquid distributing arm extending outwardly from each box, the arm having at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the weir box compartments and the other section opening into the other weir box compartment.

3. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending radially from the well, an upwardly extending weir dividing the box into two longitudinal compartments, one of the compartments opening directly into the well, and the other being sealed from direct communication with the well, and a liquid distributing arm extending outwardly from the box, the arm having at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the weir box compartments and the other section opening into the other weir box compartment.

4. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending outwardly from the well, an upwardly extending Weir dividing the box into two compartments, one of the compartments opening directly into the well, a liquid distributing arm extending outwardly from the box, and a curved partition having an upright upper portion in the arm dividing the arm into at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the weir box compartments and the other section opening into the other weir box compartment.

5. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending outwardly from the well, the weir box having an opening to permit discharge of liquid in a lateral direction, an upwardly extending weir dividing the box into two compartments, one of the compartments opening directly into the well, and a liquid distributing arm extending outwardly from the box, the arm having at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the weir box compartments and the other section opening into the other weir box compartment.

6. In a rotary liquid distributor having a hollow central 65 well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending outwardly from the well, an upwardly extending longitudinal weir dividing the box into two compartments, the lower portion of the weir being curved in the direction opposite to the rotation of the well to seal against the weir box interior, one of the compartments opening directly into the well, and a liquid distributing arm extending outwardly from the box, the arm having at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the weir box compartments and the other section opening into the other weir box compartment.

7. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending outwardly from the well, an upwardly extending weir dividing the box into two compartments, one of the compartments opening directly into the well, and a liquid distributing arm extending outwardly from the box, a partition in the arm dividing it into a leading longitudinal flow section and into a trailing longitudinal flow section, each of the sections being provided with a plurality of spaced liquid discharge openings, the trailing section opening into the weir box compartment which opens directly into the well and the leading section opening into the other weir box compartment.

8. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending outwardly from the well, an upwardly extending weir dividing the box into two compartments, one of the compartments opening directly into the well, a vertically adjustable strip attached to the upper edge of the weir whereby the effective height of the weir can be regulated, and a liquid distributing arm extending outwardly from the box, the arm having at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the Weir box compartments and the other section opening into the other weir box compartment.

9. In a rotary liquid distributor having a hollow central well adapted to receive liquid and rotate on a base, the combination comprising a weir box attached to and extending outwardly from the well, an upwardly extending weir dividing the box into two compartments, one of the compartments opening directly into the well, a valve-controlled orifice in the intermediate portion of the weir, and a liquid distributing arm extending outwardly from the box, the arm having at least two longitudinal flow sections separately provided with a plurality of spaced liquid discharge openings, one of the sections opening into one of the weir box compartments and the other section opening into the other weir box compartment.

References Cited in the file of this patent UNITED STATES PATENTS 754,953 Williams et al. Mar. 15, 1904 2,181,932 Beddocs Dec. 5, 1939 FOREIGN PATENTS 21,882 Great Britain Oct. 31, 1902 

